Every California House a Zero Net Energy Building?

Every home in California will have to be zero net energy or better by 2020 if a California assemblywoman has her way. San Diego Democrat Lori Saldana's bill would require homes to emit no carbon and give power back into the grid.

The excess power would come from renewable energy sources, like solar polar panels. It could be generated by nearby wind or geothermal plants, too. The bill will go through Assembly Natural Resources Committee.

Saldana's legislation would require new homes to meet zero net energy requirements by Jan. 1, 2020, or when the California Energy Commission determines that use of solar systems is cost-effective, whichever comes later.

Del Chiaro (Environment California) said she expects that currently available state rebates and federal tax breaks will create enough of a mainstream market for solar systems over the next 10 years to cut their cost in half.

Saldana said her bill would help cut the emissions blamed for global warming by reducing dependence on fossil fuels.

"About a quarter of greenhouse gas emissions are related to buildings--heating and cooling them," she said. "Looking at ways to build smarter will have significant and beneficial impacts on reducing greenhouse gases and avoiding more impacts of climate change."

The bill comes as the state is dealing with the challenge of getting roughly a third of its energy from renewable resources. Yesterday, in a remarkable announcement, CA utility Pacific Gas and Electric announced that it would buy solar power from space. The deal will help PG&E; meet their state-mandated commitment.